Average Error: 34.7 → 6.6
Time: 6.4s
Precision: binary64
\[\frac{\left(-b_2\right) + \sqrt{b_2 \cdot b_2 - a \cdot c}}{a}\]
\[\begin{array}{l} \mathbf{if}\;b_2 \leq -1.059261012864539 \cdot 10^{+51}:\\ \;\;\;\;0.5 \cdot \frac{c}{b_2} - 2 \cdot \frac{b_2}{a}\\ \mathbf{elif}\;b_2 \leq 1.0864668519398205 \cdot 10^{-267}:\\ \;\;\;\;\frac{\sqrt{b_2 \cdot b_2 - c \cdot a} - b_2}{a}\\ \mathbf{elif}\;b_2 \leq 1.836614570390093 \cdot 10^{+147}:\\ \;\;\;\;\frac{-c}{b_2 + \sqrt{b_2 \cdot b_2 - c \cdot a}}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{0.5 \cdot \frac{a}{b_2} - 2 \cdot \frac{b_2}{c}}\\ \end{array}\]
\frac{\left(-b_2\right) + \sqrt{b_2 \cdot b_2 - a \cdot c}}{a}
\begin{array}{l}
\mathbf{if}\;b_2 \leq -1.059261012864539 \cdot 10^{+51}:\\
\;\;\;\;0.5 \cdot \frac{c}{b_2} - 2 \cdot \frac{b_2}{a}\\

\mathbf{elif}\;b_2 \leq 1.0864668519398205 \cdot 10^{-267}:\\
\;\;\;\;\frac{\sqrt{b_2 \cdot b_2 - c \cdot a} - b_2}{a}\\

\mathbf{elif}\;b_2 \leq 1.836614570390093 \cdot 10^{+147}:\\
\;\;\;\;\frac{-c}{b_2 + \sqrt{b_2 \cdot b_2 - c \cdot a}}\\

\mathbf{else}:\\
\;\;\;\;\frac{1}{0.5 \cdot \frac{a}{b_2} - 2 \cdot \frac{b_2}{c}}\\

\end{array}
(FPCore (a b_2 c)
 :precision binary64
 (/ (+ (- b_2) (sqrt (- (* b_2 b_2) (* a c)))) a))
(FPCore (a b_2 c)
 :precision binary64
 (if (<= b_2 -1.059261012864539e+51)
   (- (* 0.5 (/ c b_2)) (* 2.0 (/ b_2 a)))
   (if (<= b_2 1.0864668519398205e-267)
     (/ (- (sqrt (- (* b_2 b_2) (* c a))) b_2) a)
     (if (<= b_2 1.836614570390093e+147)
       (/ (- c) (+ b_2 (sqrt (- (* b_2 b_2) (* c a)))))
       (/ 1.0 (- (* 0.5 (/ a b_2)) (* 2.0 (/ b_2 c))))))))
double code(double a, double b_2, double c) {
	return (-b_2 + sqrt((b_2 * b_2) - (a * c))) / a;
}
double code(double a, double b_2, double c) {
	double tmp;
	if (b_2 <= -1.059261012864539e+51) {
		tmp = (0.5 * (c / b_2)) - (2.0 * (b_2 / a));
	} else if (b_2 <= 1.0864668519398205e-267) {
		tmp = (sqrt((b_2 * b_2) - (c * a)) - b_2) / a;
	} else if (b_2 <= 1.836614570390093e+147) {
		tmp = -c / (b_2 + sqrt((b_2 * b_2) - (c * a)));
	} else {
		tmp = 1.0 / ((0.5 * (a / b_2)) - (2.0 * (b_2 / c)));
	}
	return tmp;
}

Error

Bits error versus a

Bits error versus b_2

Bits error versus c

Try it out

Your Program's Arguments

Results

Enter valid numbers for all inputs

Derivation

  1. Split input into 4 regimes
  2. if b_2 < -1.05926101286453896e51

    1. Initial program 37.3

      \[\frac{\left(-b_2\right) + \sqrt{b_2 \cdot b_2 - a \cdot c}}{a}\]
    2. Simplified37.3

      \[\leadsto \color{blue}{\frac{\sqrt{b_2 \cdot b_2 - a \cdot c} - b_2}{a}}\]
    3. Taylor expanded around -inf 5.7

      \[\leadsto \color{blue}{0.5 \cdot \frac{c}{b_2} - 2 \cdot \frac{b_2}{a}}\]

    if -1.05926101286453896e51 < b_2 < 1.0864668519398205e-267

    1. Initial program 9.9

      \[\frac{\left(-b_2\right) + \sqrt{b_2 \cdot b_2 - a \cdot c}}{a}\]
    2. Simplified9.9

      \[\leadsto \color{blue}{\frac{\sqrt{b_2 \cdot b_2 - a \cdot c} - b_2}{a}}\]

    if 1.0864668519398205e-267 < b_2 < 1.83661457039009296e147

    1. Initial program 36.8

      \[\frac{\left(-b_2\right) + \sqrt{b_2 \cdot b_2 - a \cdot c}}{a}\]
    2. Simplified36.8

      \[\leadsto \color{blue}{\frac{\sqrt{b_2 \cdot b_2 - a \cdot c} - b_2}{a}}\]
    3. Using strategy rm
    4. Applied flip--_binary6436.8

      \[\leadsto \frac{\color{blue}{\frac{\sqrt{b_2 \cdot b_2 - a \cdot c} \cdot \sqrt{b_2 \cdot b_2 - a \cdot c} - b_2 \cdot b_2}{\sqrt{b_2 \cdot b_2 - a \cdot c} + b_2}}}{a}\]
    5. Simplified16.2

      \[\leadsto \frac{\frac{\color{blue}{-a \cdot c}}{\sqrt{b_2 \cdot b_2 - a \cdot c} + b_2}}{a}\]
    6. Simplified16.2

      \[\leadsto \frac{\frac{-a \cdot c}{\color{blue}{b_2 + \sqrt{b_2 \cdot b_2 - a \cdot c}}}}{a}\]
    7. Using strategy rm
    8. Applied *-un-lft-identity_binary6416.2

      \[\leadsto \frac{\frac{-a \cdot c}{b_2 + \sqrt{b_2 \cdot b_2 - a \cdot c}}}{\color{blue}{1 \cdot a}}\]
    9. Applied *-un-lft-identity_binary6416.2

      \[\leadsto \frac{\frac{-a \cdot c}{\color{blue}{1 \cdot \left(b_2 + \sqrt{b_2 \cdot b_2 - a \cdot c}\right)}}}{1 \cdot a}\]
    10. Applied *-un-lft-identity_binary6416.2

      \[\leadsto \frac{\frac{\color{blue}{1 \cdot \left(-a \cdot c\right)}}{1 \cdot \left(b_2 + \sqrt{b_2 \cdot b_2 - a \cdot c}\right)}}{1 \cdot a}\]
    11. Applied times-frac_binary6416.2

      \[\leadsto \frac{\color{blue}{\frac{1}{1} \cdot \frac{-a \cdot c}{b_2 + \sqrt{b_2 \cdot b_2 - a \cdot c}}}}{1 \cdot a}\]
    12. Applied times-frac_binary6416.2

      \[\leadsto \color{blue}{\frac{\frac{1}{1}}{1} \cdot \frac{\frac{-a \cdot c}{b_2 + \sqrt{b_2 \cdot b_2 - a \cdot c}}}{a}}\]
    13. Simplified16.2

      \[\leadsto \color{blue}{1} \cdot \frac{\frac{-a \cdot c}{b_2 + \sqrt{b_2 \cdot b_2 - a \cdot c}}}{a}\]
    14. Simplified7.1

      \[\leadsto 1 \cdot \color{blue}{\frac{-c}{b_2 + \sqrt{b_2 \cdot b_2 - a \cdot c}}}\]

    if 1.83661457039009296e147 < b_2

    1. Initial program 63.3

      \[\frac{\left(-b_2\right) + \sqrt{b_2 \cdot b_2 - a \cdot c}}{a}\]
    2. Simplified63.3

      \[\leadsto \color{blue}{\frac{\sqrt{b_2 \cdot b_2 - a \cdot c} - b_2}{a}}\]
    3. Using strategy rm
    4. Applied flip--_binary6463.3

      \[\leadsto \frac{\color{blue}{\frac{\sqrt{b_2 \cdot b_2 - a \cdot c} \cdot \sqrt{b_2 \cdot b_2 - a \cdot c} - b_2 \cdot b_2}{\sqrt{b_2 \cdot b_2 - a \cdot c} + b_2}}}{a}\]
    5. Simplified38.6

      \[\leadsto \frac{\frac{\color{blue}{-a \cdot c}}{\sqrt{b_2 \cdot b_2 - a \cdot c} + b_2}}{a}\]
    6. Simplified38.6

      \[\leadsto \frac{\frac{-a \cdot c}{\color{blue}{b_2 + \sqrt{b_2 \cdot b_2 - a \cdot c}}}}{a}\]
    7. Using strategy rm
    8. Applied clear-num_binary6438.6

      \[\leadsto \color{blue}{\frac{1}{\frac{a}{\frac{-a \cdot c}{b_2 + \sqrt{b_2 \cdot b_2 - a \cdot c}}}}}\]
    9. Simplified38.1

      \[\leadsto \frac{1}{\color{blue}{\left(b_2 + \sqrt{b_2 \cdot b_2 - a \cdot c}\right) \cdot \frac{1}{-c}}}\]
    10. Taylor expanded around inf 1.8

      \[\leadsto \frac{1}{\color{blue}{0.5 \cdot \frac{a}{b_2} - 2 \cdot \frac{b_2}{c}}}\]
  3. Recombined 4 regimes into one program.
  4. Final simplification6.6

    \[\leadsto \begin{array}{l} \mathbf{if}\;b_2 \leq -1.059261012864539 \cdot 10^{+51}:\\ \;\;\;\;0.5 \cdot \frac{c}{b_2} - 2 \cdot \frac{b_2}{a}\\ \mathbf{elif}\;b_2 \leq 1.0864668519398205 \cdot 10^{-267}:\\ \;\;\;\;\frac{\sqrt{b_2 \cdot b_2 - c \cdot a} - b_2}{a}\\ \mathbf{elif}\;b_2 \leq 1.836614570390093 \cdot 10^{+147}:\\ \;\;\;\;\frac{-c}{b_2 + \sqrt{b_2 \cdot b_2 - c \cdot a}}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{0.5 \cdot \frac{a}{b_2} - 2 \cdot \frac{b_2}{c}}\\ \end{array}\]

Reproduce

herbie shell --seed 2020280 
(FPCore (a b_2 c)
  :name "quad2p (problem 3.2.1, positive)"
  :precision binary64
  (/ (+ (- b_2) (sqrt (- (* b_2 b_2) (* a c)))) a))